Circular knitting machine for the manufacture of stockings



1955 P. GlUlUZZA ETAL 3,221,516

CIRCULAR KNITTING MACHINE FOR THE MANUFACTURE OF STOCKINGS Filed Dec. 14, 1961 6 Sheets-Sheet 1 1965 P. GIUIUZZA ETAL 3,221,516

CIRCULAR KNITTING MACHINE FOR THE MANUFACTURE OF STOCKINGS Filed Dec. 14, 1961 6 Sheets-Sheet 2 A V O Dec. 7, 1965 P. GIUIUZZA ETAL 3,221,516

CIRCULAR KNITTING MACHINE FOR THE MANUFACTURE OF STOCKINGS Filed Dec. 14, 1961 6 Sheets-Sheet 3 1965 P. GlUlUZZA ETAL CIRCULAR KNITTING MACHINE FOR THE MANUFACTURE OF STOCKINGS 6 Sheets-Sheet 4 Filed Dec. 14, 1961 Dec. 7, 1965 P. GIUIUZZA ETAL CIRCULAR KNITTING MACHINE FOR THE MANUFACTURE OF STOCKINGS Filed Dec.

6 Sheets-Sheet 5 l 1 l I l 7, 1955 P. GIUIUZZA ETAL 3,221,516

CIRCULAR KNITTING MACHINE FOR THE MANUFACTURE OF STOCKINGS Filed Dec. 14, 1961 6 Sheets-Sheet 6 United States Patent 3,221,516 CIRCULAR KNITTING MACHINE FOR THE MANUFACTURE OF STUCK KINGS Pietro Giuiuzza and Arduino Schoen, Milan, Italy, as-

signors, by direct and mesne assignments, to 0.M.C.S.A. Otticine Meccaniche Cigardi S.p.A., Milan, Italy, an Italian company Filed Dec. 14, 1961, Ser. No. 159,297 Claims priority, application Italy, Dec. 19, 1960, Patent 641,962 3 Claims. (Cl. 668) The present invention relates to circular knitting machines for making stockings.

As is known, these machines are provided with a needle cylinder formed with longitudinal slits wherein needles,

adapted for being raised and lowered, are controlled by appropriate cams located in a cam box. The needle cylinder rotates on its own axis so as to form the knitted fabric in co-operation with the sinkers. The number of sinkers is equal to the number of the needles, and said sinkers are, in turn, movable within radial slits in a sinker-holding ring integral with the needle cylinder.

In machines designed for the manufacture of ladies stockings with automatic double edges, there is further provided a disc, axially disposed above the needle cylinder and also fitted with radial slits wherein are disposed hooks for retaining the first rows of the fabric during the knitting of the double edge and then to take these first rows back to the leg when the edge is finished. The needle cylinder normally has a continuous rotary motion about its own axis, but during the phase of making the heel and the toe of the stockings, the continuous rotary motion is changed into a reciprocating rotary motion.

In order to increase the output from a machine of the above type, a system of multiple feeds has been adopted, so that at each complete revolution of the needle cylinder, a plurality of rows and, more precisely, as many rows as there are feeds, are made. This system is commonly used in knitting machines with large needle cylinder diameters, while in machines for the manufacture of stockings in which the diameter of the needle cylinder is very limited, the number of feeds cannot exceed a certain limit dictated by obvious reasons of space.

Since the limit placed on the number of feeds in circular machines for the manufacture of stockings cannot be exceeded because of the limited space available and since also the number of revolutions per minute of the needle cylinder in modern machines has already reached a maximum which it would be difficult to exceed without impairing the proper working of the machine, other solutions are necessary in order to obtain any further increase in the productivity of the machines Without lowering their performance.

One of the main objects of the present invention is to greatly increase the output of machines of the above type by multiplying the output by an integer, as for example, doubling or tripling the output.

This result is obtained according to the invention by providing in one machine, a plurality of needle cylinders with related mechanisms for forming the knitted fabric, and by arranging for a centralized drive for these needle cylinders with their hook discs, together with a simultaneous control for all the mechanisms, associated with the several needle cylinders, which determine the work cycle.

In practice, according to the invention, two, three or more machines of conventional type have been grouped together in a single machine, With but a single driving means to impart rotary motion, either continuous or reciprocating, to the several needle cylinders and discs, and preferably a single control for the work cycle of all 3,221,516 Patented Dec. 7, 1965 ICC the needle cylinders working in synchronization with each other.

Numerous problems are solved by the above, and a series of important advantages are obtained.

In the first place, it may be seen that the machine according to the invention is capable of manufacturing simultaneously two, three or more stockings, thus doubling, tripling, etc. the output as though two, three or more machines were employed. But by grouping together the several work heads (needle cylinders) in a single machine, and giving them a single drive, there is obtained not only a very great saving in cost in comparison with the total cost of two, three or more separate machines, but also a considerable saving in space since the machine according to the invention takes up much less room than several conventional machines.

Another advantage of great importance is that, with the machine according to the invention, several identical stockings can be knitted simultaneously. For example, with a two-drum machine, in one work cycle a pair of stockings is obtained with exactly identical measurements and characteristics. By contrast, this result cannot be obtained with a plurality of separate machines which in practice can never be adjusted with such precision as to produce perfectly identical stockings. But even stockings made by a single machine are never perfectly identical since, in the course of time, variable factors such as, for example, environmental conditions and voltage drops in the supply to the electric motor driving the machine, come into play and often produce the result that stockings successively manufactured on the same machine do not exactly correspond to each other in their measurements.

This drawback is completely eliminated in the machine according to the invention, since with a single control means for the work cycle, said machine produces simultaneously a plurality of stockings which are identical. In the machine according to the invention, each head or needle cylinder can work with one or more feeds. If, for example, there are two needle cylinders each with two feeds, there is provided four feeds (2 2=4) which, unlike the four-feed machines hitherto known, are able to construct complete stockings with heels and toes, since it is also provided with reciprocating motion.

Although the several drums grouped together in the machine can be arrenged in any suitable manner, a particularly advantageous arrangement of the drums is that of a circle with a central drive shaft from which both the rotary movements of the needle cylinders, and the synchronized movements of the hook discs, of the several heads or units, can be derived.

The controls for the mechanisms associated with the needle cylinders, which determine the work cycle, e.g. thread guides, cams and any pattern devices, etc., are derived from one or more common control mechanisms, such as a control drum, which determine at each instant an identical position of the corresponding parts of the several heads. It is understood that each unit can be provided with all the members, mechanisms and devices which might be useful or necessary for the making of a stocking.

For the sake of greater clarity of the new motion involved herein, there shall now be described in the accompanying drawing tWo embodiments of the invention, which are purely illustrative and exemplary and do not limit the scope of the invention.

All said drawings are diagrammatic and do not show in detail the actual mechanisms and devices which cooperate in the knitting of the fabric in the individual heads. It is understood that these mechanisms, which do not differ from those normally used in conventional machines, are of common knowledge to those skilled in the art.

FIG. 1 is a front diagrammatic view of a two-cylinder machine according to the invention, with a horizontal drive shaft;

FIG. 2 is a plan view of the same machine, and

FIG. 3 is a schematic side view;

FIG. 4 like FIG. 1, shows a two-cylinder machine with a vertical drive shaft;

FIG. 5 is a diagrammatic side view of the machine shown in FIG. 4, and

FIG. 6 shows diagrammatically the transmission mechanisms of the vertical drive shaft machine.

With reference to FIGURES 1 to 3, therein is shown a circular stocking-knitting machine with two needle cylinders 1 and 2 arranged on parallel vertical axes, symmetrically in respect to the center of the machine. These needle cylinders can rotate, each on its own axis, and are fitted on to inner tubes 3 and 4 respectively. Integral with these tubes there are gears 5 and 6 with helical teeth, which are in mesh with a central gear 7 fastened to vertical shaft 8 disposed between the two drums 1 and 2. At its top end, vertical shaft 8 carries a bevel gear 9 with which two horizontal bevel gears 10 and 11 are in mesh. The bevel gears 10 and 11 are integral respectively with shafts 12 and 13 which are revolvably supported in the two caps 14 and 15 of the two needle cylinders. On each of said horizontal shafts 12 and 13 there is fastened second bevel gears, 16 and 17 respectively, which meshes with beveled gears 18 and 19, the latter being respectively integral with vertical shafts 20 and 21. The two shafts 20 and 21 also revolve in the caps of the two heads and carry at their bottom ends, hook discs 22 and 23 which are co-axial with the respective needle cylinders 2 and 1.

It can be seen that the central vertical shaft 8 drives, simultaneously and in synchronization, the two needle cylinders 1 and 2 and their respective hook discs 23 and 22.

The central vertical shaft 8 is in turn driven by horizontal driving shaft 24, through a direct coupling 25 and helical gear combination 26-27.

The numeral 28 indicates the handle for the initial adjustment of the machine and for turning the needle cylinders by hand, as on ordinary machines.

Wheel 29 meshes with a toothed sector 30 (shown schematically only in FIG. 1) to bring about the reciprocating rotary motion during the phase of constructing the heels and toes of the stockings.

In FIG. 1, and particularly in FIG. 3, there is shown one of the central control drums 31 which carries a series of annular cams for controlling and governing the entire work cycle of the machine.

With each annular cam, e.g. cam 32 shown in FIG. 3, there is associated a lever 33 pivoted on a small bracket of the machine frame and elastically pressing against the surface of control drum 31. A pin 34 supported in bracket 35 so as to allow axial movement thereof, rests on the lever 33. Pin 34 carries at its end a rocker 36 whereon there rest the ends of two flexible rods 37, 38 which control with their other ends two corresponding mechanisms associated with the two needle cylinders 1 and 2, e.g. two thread guides, two corresponding cams in the cam box, etc.

Thus a common cam 32 on control drum 31 simultaneously actuates two mechanisms having identical functions, but one associated with one needle cylinder and the other with the second needle cylinder, thus ensuring synchronism of control of the work cycles of the two needle cylinders.

Referring now to the embodiment illustrated in FIG- URES 4 to 6, the two needle cylinders 1 and 2 fitted over tubes 3 and 4, are driven by the same central spur gear 7 which meshes respectively with crown gears 5 and 6, and is integral with the central vertical shaft 8. The only difference from the embodiment described hereinbefore is that the driving shaft 24 has a vertical axis and is a direct extension of shaft 8 with which it is coupled by means of direct coupling 25. The reciprocating rotary motion is transmitted to shaft 8 through gear 29 which is in engagement with toothed sector 30 which swings on pivot 40 on the machine frame. Sector 30 is caused to swing by means of a toothed wheel 41 which meshes with toothed wheel 42 which is integral with driving shaft 24 and to which a connecting rod 43 is eccentrically pivoted, said connecting rod being attached at its other end to sector 30 (see FIGURES 5 and 6).

In addition, a toothed wheel 44, connected through intermediate gearing to handle 28, is also in engagement with toothed wheel 41.

In other respects the operation of this machine is similar to that of the machine first described. The invention has been described for illustrative and non-limiting purposes, with reference to two practical embodiments thereof.

It is understood, however, that numerous variants are possible within the range of the invention without departing from the following claims.

We claim:

1. A knitting machine for the manufacture of stockings comprising a plurality of parallel needle cylinders each adapted for rotation about a vertical axis, each cylinder including knitting means adapted for the knitting of fabric, central drive means for said needle cylinders for driving the same together and simultaneously, and means for controlling the knitting means of each of the needle cylinders simultaneously to produce identical stockings from each needle cylinder, the latter said means comprising a control drum, a plurality of cams on said drum and means associated with the cams on said control drum and the knitting means of each of the needle cylinders for controlling the knitting means simultaneously from the control drum, the latter means comprising a lever for each cam resiliently urged thereagainst, a rocker for each lever, a rod for each of the knitting means coupled to the rocker for controlling the associated knitting means, and means for moving each of the rockers and the rods coupled thereto upon corresponding movement of the associated lever.

2. A machine as claimed in claim 1 wherein the means for moving each of the rockers upon corresponding movement of the associated lever comprises a pin for each lever supported thereon and in turn in contact with the associated rocker.

3. A machine as claimed in claim 2 wherein said pin is vertically supported, the machine comprising a bracket slidably supporting the pin.

References Cited by the Examiner UNITED STATES PATENTS 360,735 4/ 1887 Schroeder et al. 668

472,029 4/ 1892 Cathcart et al 66154 X 2,731,572 1/1956 Cobert 6614 2,860,499 11/1958 Marum 6614 FOREIGN PATENTS 202,019 9/ 1908 Germany.

3,968 8/1882 Great Britain. 500,189 11/1954 Italy.

DONALD W. PARKER, Primary Examiner.

RUSSELL C. MADER, Examiner. 

1. A KNITTING MACHINE FOR THE MANUFACTURE OF STOCKINGS COMPRISING A PLURALITY OF PARALLEL NEEDLE CYLINDERS EACH ADAPTED FOR ROTATION ABOUT A VERTICAL AXIS, EACH CYLINDER INCLUDING KNITTING MEANS ADAPTED FOR THE KNITTING OF FABRIC CENTRAL DRIVE MEANS FOR SAID NEEDLE CYLINDERS FOR DRIVING THE SAME TOGETHER AND SIMULTANEOUSLY, AND MEANS FOR CONTROLLING THE KNITTING MEANS FOR EACH OF THE NEEDLE CYLINDERS SIMULTANEOUSLY TO PRODUCE IDENTICAL STOCKINGS FROM EACH NEEDLE CYLINDER, THE LATTER SAID MEANS COMPRISING A CONTROL DRUM, A PLURALITY OF CAMS ON SAID DRUM AND MEANS ASSOCIATED WITH THE CAMS ON SAID CONTROL DRUM AND THE KNITTING MEANS OF EACH OF THE NEEDLE CYLINDERS FOR CONTROLLING THE KNITTING MEANS SIMULTANEOUSLY FROM THE CONTROL DRUM, THE LATTER MEANS COMPRISING A LEVER FOR EACH CAM RESILIENTLY URGED THEREAGAINST, A ROCKER FOR EACH LEVER, A ROD FOR EACH OF THE KNITTING MEANS COUPLED TO THE ROCKER FOR CONTROLLING THE ASSOCIATED KNITTING MEANS, AND MEANS FOR MOVING EACH OF THE ROCKERS AND THE RODS COUPLED THERETO UPON CORRESPONDING MOVEMENT OF THE ASSOCIATED LEVER. 